Patents by Inventor Joshua Shefer

Joshua Shefer has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Electron gun with improved beam forming region
    Patent number: 4409514
    Abstract: An electron gun for use in a cathode ray tube includes beam forming electrodes and beam focusing electrodes. A gun improvement comprises the beam forming electrodes including a cathode, a control grid adjacent to the cathode and two screen grids. A first screen grid is located adjacent to the control grid. A second screen grid is located between the first screen grid and the beam focusing electrodes. Preferably, the second screen grid and the control grid are grounded.
    Type: Grant
    Filed: April 29, 1981
    Date of Patent: October 11, 1983
    Assignee: RCA Corporation
    Inventors: Joshua Shefer, Carmen A. Catanese